TWI540343B - Display with blue pigment layer under black matrix - Google Patents

Description

Display with blue pigment layer under black matrix

The present application claims priority to PCT International Patent Application No. PCT/US13/46182, filed on Jun. 17, 2013, which is hereby incorporated by reference in its entirety.

The present invention relates generally to displays, and more particularly to displays having color filter layers.

Electronic devices such as computers and handheld electronic devices have displays such as liquid crystal displays. Liquid crystal displays typically have a rectangular central active area surrounded by an annular inactive area. The display pixel array in the active area is used to display an image to the user. A color filter layer formed from an array of color filter elements, such as red, blue, and green pigments, is used to provide the display with the ability to display color images. The color filter layer includes a black mask in the inactive area.

The black mask is formed of a polymeric black masking layer and is used to hide the internal display components from view. The portions of the black masking layer are used to create a grid-like black matrix in the active area of the display. The black matrix has a rectangular opening that is covered by a color filter element.

In some color filter layer configurations, a black matrix is formed on the surface of the color filter substrate prior to deposition of the color filter elements. This situation can result in an undesirable amount of reflected light from the black matrix during use of the display. Forming a black matrix after patterning the color filter elements onto the color filter substrate, adjacent to the color filter elements A reduced amount of black matrix is formed in the space between the pieces, thereby reducing black matrix reflection. However, if not careful, the black matrix reflection may still be greater than desired.

Therefore, it is desirable to be able to reduce black matrix reflections in the color filter layer of the display.

A liquid crystal display can be provided with a color filter layer and a thin film transistor layer. The color filter layer may have a glass substrate covered with a color filter element structure. The thin film transistor layer may have a glass substrate covered with a thin film transistor circuit. A layer of liquid crystal material can be interposed between the color filter layer and the thin film transistor layer. Upper and lower polarizing layers may be formed above and below the color filter layer and the thin film transistor layer.

The display can have an active area with a display pixel array. An inactive area can surround the active area. A black mask structure can be formed in the inactive area. A black matrix having a mesh shape having one of rectangular openings may be formed in the active region.

Red, green, and blue filter elements can overlap the rectangular openings of the black matrix. The black matrix may have a first layer formed by a blue photoresist grid deposited directly and patterned on one of the inner surfaces of the color filter substrate, and may have a grid formed by a black photoresist alignment One of the second layers. Edge portions of the color filter elements can be inserted between the blue photoresist grid and the black photoresist grid.

In the inactive region, the black mask structure may be formed by a blue photoresist layer covered with a black photoresist layer.

Other features, aspects, and advantages of the invention will be apparent from the description and appended claims.

10‧‧‧Electronic devices

12‧‧‧Input and output circuits

14‧‧‧ display

16‧‧‧Input and output devices

18‧‧‧Storage and processing circuits

20‧‧‧ display pixels

22‧‧‧Backlight unit

24‧‧‧ Backlight

26‧‧‧lower polarizer

28‧‧‧ glass substrate

30‧‧‧Thin-film transistor circuit layer

30E‧‧‧Metal display pixel electrode

32‧‧‧Thin film transistor layer

34‧‧‧Liquid layer

36‧‧‧Color filter structure

38‧‧‧Black masking material

38AA‧‧‧Black matrix/material/black masking material/black photoresist/black matrix material/black Color photoresist grid/layer

38IA‧‧‧Black matte/material/black photoresist strip/layer

40‧‧‧Color filter components

40B‧‧‧Material/layer/blue filter component/blue photoresist structure

40B'‧‧‧ Zone/Layer/Blue Resistor Structure/Boundary Section/Blue Filter Component Material

40B"‧‧‧ areas/blue filter material/layer/blue photoresist/blue photoresist structure/grid pattern

40G‧‧‧Green filter component structure

40R‧‧‧Red filter component structure

42‧‧‧Glass substrate/color filter layer substrate

44‧‧‧Color filter layer

46‧‧‧Upper polarizer

47‧‧‧Indium tin oxide layer

49‧‧‧Transparent finish

50‧‧‧Inner/inner surface

52‧‧‧Viewer

54‧‧‧ Direction

61‧‧‧ vertical line

63‧‧‧ vertical line

65‧‧‧ vertical line

AA‧‧‧ area of action

D‧‧‧ data line

G‧‧‧ gate line

IA‧‧‧inactive area

Z‧‧‧ direction

1 is a schematic diagram of an electronic device of the type that can be provided with a display in accordance with an embodiment of the present invention.

2 is a diagram of an illustrative display pixel array in a display in accordance with an embodiment of the present invention.

3 is a cross-sectional side view of an illustrative display in accordance with an embodiment of the present invention.

4 is a top plan view of a portion of a color filter for a display in accordance with an embodiment of the present invention.

5 is a cross-sectional side view showing a portion of a display that can form a color filter layer structure in accordance with an embodiment of the present invention.

An illustrative electronic device of the type that can be provided with a display is shown in FIG. An electronic device such as the illustrative electronic device 10 of FIG. 1 can be a laptop, tablet, cellular phone, media player, other handheld and portable electronic devices, such as wristwatch devices, pendant devices, headsets Headphones and earpieces, smaller devices for other wearable and small devices, or other electronic devices.

As shown in FIG. 1, device 10 can include storage and processing circuitry 18 and input and output circuitry 12. The storage and processing circuitry 18 may include a storage such as a hard disk drive storage, non-volatile memory (eg, flash memory or other electrically programmable read-only memory configured to form a solid state disk), Volatile memory (eg, static or dynamic random access memory), etc. Processing circuitry in the storage and processing circuitry 18 can be used to control the operation of the apparatus 10. The processing circuit can be based on one or more microprocessors, microcontrollers, digital signal processors, special application integrated circuits, and the like.

Input and output circuitry 12 can be used to receive input from the user and the environment and can be used to supply output to the user and external devices. The input and output circuit 12 can include input and output devices 16, such as buttons, joysticks, click-selectors, scroll wheels, trackpads, keypads, keyboards, microphones, cameras, buttons, speakers, status indicators, light sources, audio jacks. And other audio components, digital data devices, optical sensors, motion sensors (accelerometers), capacitive sensors, proximity sensors, wireless and wired communication circuits. Input and output circuitry 12 may also include a display such as display 14. Display 14 can be a touch screen display or can be a display that is insensitive to touch input. Example package for touch screen display A display having an array of capacitive touch sensor electrodes. Other types of touch sensor arrays can be incorporated into display 14 as needed.

Display 14 can be a liquid crystal display having a display pixel array such as display pixel 20 of FIG. Each of the pixels 20 may have circuitry, electrodes, and storage capacitors, such as thin film transistor circuits, for controlling the electric field applied to corresponding portions of the liquid crystal layer. The gate line G and the data line D can be used to distribute display control signals to the display pixels 20.

A cross-sectional side view of display 14 is shown in FIG. The backlight unit 22 can be based on a fluorescent bulb or a light emitting diode array. Backlight unit 22 may generate backlight 24 that travels vertically through the display layer of display 14 in direction Z.

Display 14 includes a lower polarizer 26 and an upper polarizer 46. A circuit (e.g., an electrode) that displays pixel 20 is used to control the electric field applied to liquid crystal layer 34. By controlling the electric field, the liquid crystal layer can control the polarization of the light 24 in each display pixel as it passes through the liquid crystal layer 34, thereby controlling the brightness of each pixel 20.

The liquid crystal layer 34 is sandwiched between the thin film transistor layer 32 and the color filter layer 44. The thin film transistor layer 32 includes a transparent substrate such as a glass substrate 28, and a thin film transistor circuit layer 30 (for example, a polycrystalline germanium and/or amorphous germanium transistor, a pixel electrode, a gate line, a data line, etc.).

The color filter layer 44 includes a transparent substrate such as a glass substrate 42. Display 14 can have a rectangular shape. The rectangular center area (which is sometimes referred to as the active area AA) may contain a rectangular array of display pixels 20 and may be used to display an image to a user. A rectangular annular inactive boundary region (which is sometimes referred to as a non-active region IA) may surround the active region AA.

Color filter layer 44 can include a layer of color filter structures 36 on substrate 42. In the inactive area IA, the color filter structure 36 can include a strip of opaque masking material (such as black masking material 38) that forms an opaque border known as a black mask. In the active area AA, the color filter structure 36 can include an array of color filter elements 40. The material used to form the black masking material 38 and the color filter element 40 may be a colored polymer (ie, The black photoresist for material 38, and the colored photoresist for color filter elements 40 such as red, green, and blue photoresists.

4 is a top plan view of an illustrative portion of color filter layer structure 36. In the inactive area IA, the black masking material 38 can be used to form an opaque boundary structure such as a black mask 38IA. In the active area AA, color filter elements 40 such as red (R), green (G), and blue (B) filter elements can be organized into an array having a plurality of element columns and component rows. Portions of the black masking material 38 can be used to form an opaque grid between the individual color filter elements to help reduce bleed between adjacent pixels. An opaque grid formed using black masking material 38 may sometimes be referred to as a black matrix. As shown in FIG. 4, the black matrix 38AA forms a grid having a series of rectangular openings, each of which overlaps with the respective color filter element 40.

A cross-sectional side view of display 14 is shown in FIG. 5, which shows how color filter element structure 36 can be configured to reduce undesirable black shading material reflections from the surface of display 14. As shown in FIG. 5, an indium tin oxide layer 47 (eg, a shielding layer) can be interposed between the upper polarizer 46 and the color filter layer substrate 42. Other layers (eg, anti-reflective coatings, anti-fouling layers, etc.) can be incorporated into display 14 as needed. The thin film transistor layer 32 may include a metal display pixel electrode 30E on the glass substrate 28. Electrode 30E is associated with display pixel 20 and is used to apply an adjustable electric field to the associated overlapping portion of liquid crystal layer 34.

The black masking material 38 can include a patterned material, such as material 38IA in the inactive area IA and material 38AA in the active area AA. The inner layer 50 of the color filter substrate 42 faces the liquid crystal layer 34. In the configuration of FIG. 5, the blue filter element material is interposed between the black masking material 38 and the inner surface 50. This situation reduces the amount of light reflected from the black mask and black matrix in the color filter layer 44 toward the viewer 52 in the direction 54 thereby enhancing the image quality on the display 14.

The blue filter material (blue photoresist) formed in the color filter layer 44 may include a material for forming a blue color filter element (for example, the rectangular color filter element 40 of FIG. 4). 40B. Material 40B can have a first thickness. The blue filter material formed in the color filter layer 44 can also include regions having a second thickness that is less than the first thickness, such as regions 40B' and 40B". Blue filter element material (eg, such as Such thinner regions of blue photoresist (blue polymer) can help reduce black masking reflections from material 38.

In the active area AA, the blue filter material 40B" may be formed in a grid aligned with the corresponding grid of the black masking material 38AA. In the active area AA, the black matrix is thus used by the blue photoresist 40B" The grid and black photoresist 38AA are formed by aligning the blue matrix layers formed by the overlapping grids.

The colored photoresist used to form layers 40B', 40B" and 40B can be deposited in one or more steps. For example, a halftone photolithographic mask can be used during photolithographic patterning operations for deposition and patterning. The blue photoresist is patterned to form a layer having a thicker portion (for color filter elements) and a thinner portion (structures 40B' and 40B"). As another example, a blue photoresist can be first deposited in a thinner patterned layer (including layers of boundary portion 40B' and grid pattern 40B", followed by deposition associated with blue filter element 40B. The second (thicker) layer.

After the blue photoresist structures 40B', 40B" and 40B are formed, other color filter elements for the color filter layer 36 can be formed. For example, after forming a blue photoresist structure, deposition and patterning can be performed The green photoresist layer is formed to form the green filter element structure 40G of FIG. 5, followed by deposition and patterning of the red photoresist layer to form the red filter element structure 40R of FIG.

As shown in FIG. 5, since the photoresist structure of the color filter layer 44 is formed in several layers, some color filter layer structures (for example, edge portions of color filter elements) and previously deposited color filters are shown. Several portions of the layer structure overlap. For example, along the vertical line 61, the blue structure 40B" is formed on the inner surface 50 of the substrate 42, the edge portion of the blue filter element 40B overlaps the blue structure 40B, and the green filter element 40G A portion of the edge overlaps the edge of the blue filter element 40B, and a portion of the black matrix material 38AA overlaps the edge of the green filter element 40G. Similarly, along the vertical line 63, blue The structure 40B" is formed on the inner surface 50 of the substrate 42, a portion of the green filter element 40G overlaps with the blue structure 40B", and a portion of the edge of the red filter element 40R overlaps the edge of the green filter element 40G. And a portion of the black matrix material 38AA overlaps the edge of the red filter element 40R. Along the vertical line 65, a blue structure 40B" is formed on the inner surface 50 of the substrate 42, a portion of the blue filter element 40B overlaps the blue structure 40B, and a portion of the edge of the red filter element 40R is blue. The edges of the color filter elements 40B overlap and one portion of the black matrix material 38AA overlaps the edges of the red filter elements 40R. Thus, there are several portions of the color filter elements interposed between the blue photoresist grid forming the black matrix and the aligned black photoresist grid.

In the illustrative configuration shown in Figure 5, the green filter element is deposited after the blue filter element and the red filter element is deposited after the green filter element. Red and green filter elements can be formed in reverse order as desired (ie, red filter elements 40R can be formed after blue filter element 40B but before green filter element 40G, such that green filtering The sheet member has an edge portion that overlaps an edge portion of the red color filter element, and an edge portion that overlaps an edge portion of the blue color filter element.

After depositing and patterning the blue, green, and red photoresist color filter layer structures, the black photoresist layer 38 can be deposited and patterned to form a black mask associated with the opaque boundary in the inactive area IA. The black photoresist strip 38IA, and the black photoresist grid 38AA in the black matrix forming the active area AA. A clear finish 49 can be deposited to cover the blue, green, and red filter elements.

The blue filter element material is used in the black mask 38IA in the inactive area IA by equalizing the reflectivity of the black mask formed by layers 38IA and 40B' and the black matrix formed by layers 40B" and 38AA. 40B' can help create a seamless transition between the inactive area IA and the active area AA.

According to an embodiment, there is provided a display having an active area surrounded by a non-active area, comprising: a thin film transistor layer; a color filter layer substrate; a layer of crystalline material interposed between the thin film transistor layer and the color filter layer substrate; a black matrix on the color filter layer substrate, the black matrix having an opening; and an array of color filter elements Each of the color filter elements overlaps with a respective one of the openings, the black matrix comprising a blue photoresist structure grid and a black photoresist structure overlap alignment grid.

In accordance with another embodiment, the display includes a black mask in the inactive area, the black mask including a blue photoresist layer overlying a black photoresist layer.

According to another embodiment, the color filter elements comprise a blue filter element, a green filter element, and a red filter element.

According to another embodiment, the green filter elements have edge portions that overlap the edge portions of the blue filter elements.

According to another embodiment, the red filter elements have edge portions that overlap the edge portions of the green filter elements.

According to another embodiment, the red filter elements have edge portions that overlap the edge portions of the blue filter elements.

According to another embodiment, the red filter elements have edge portions that overlap the edge portions of the blue filter elements.

In accordance with another embodiment, the green filter elements have edge portions that overlap the edge portions of the red filter elements and the edge portions of the blue filter elements.

According to another embodiment, the display includes an upper polarizing layer and a lower polarizing layer; the thin film transistor layer, the color filter layer substrate, and the liquid crystal layer are interposed between the upper polarizing layer and the lower polarizing layer.

In accordance with another embodiment, the display includes an indium tin oxide layer between the upper polarizer and the color filter layer substrate.

In accordance with another embodiment, the color filter layer substrate comprises a layer of glass.

In accordance with another embodiment, the thin film transistor layer includes a display pixel electrode.

According to an embodiment, a display is provided, comprising: a liquid crystal material layer; a plurality of display layers through which light passes, the display layers comprising a color filter layer substrate having an inner surface facing the liquid crystal material layer And an array of color filter elements on the inner surface, the color filter element array comprising a red filter element, a green filter element, and a blue filter element; and the color filter layer substrate a black matrix comprising a grid of blue polymeric material on the inner surface, at least some overlapping color filter component material on the grid of blue polymeric material, and the overlapping color filter A black polymer material grid on the sheet component material.

In accordance with another embodiment, the color filter component material includes edge portions of the color filter elements.

In accordance with another embodiment, the plurality of display layers have an active region comprising a display pixel array and have an inactive boundary surrounding the active region, the display further comprising a layer of blue polymeric material in the inactive boundary .

In accordance with another embodiment, the layer of blue polymeric material is formed on the inner surface, the display comprising a layer of black polymeric material on the blue polymeric material.

In accordance with another embodiment, the blue polymer material grid includes at least some blue photoresist patterned by a halftone mask.

According to an embodiment, there is provided a liquid crystal display comprising: a thin film transistor layer having a thin film transistor on a film substrate layer; a color filter layer having a color filter layer substrate; and the film a layer of liquid crystal material between the transistor layer and the color filter layer, the color filter layer comprising a black mask layer comprising a blue photoresist grid and an aligned black photoresist network The blue photoresist grid and the black photoresist grid have openings, the color filter layer comprising an array of color filter elements, the color filter elements including red and green overlapping the openings And a blue filter element, at least a portion of the color filter elements being interposed between the black photoresist grid and the blue photoresist grid, and the color filter elements and the black photoresist Grid overlay Finishing layer.

In accordance with another embodiment, the openings comprise a rectangular opening and the blue filter element comprises an edge portion between the blue photoresist grid and the black photoresist grid.

In accordance with another embodiment, the liquid crystal display includes a polarizer and an indium tin oxide layer between the polarizer and the color filter substrate layer.

The foregoing is merely illustrative of the principles of the invention, and various modifications may be made by those skilled in the art without departing from the scope of the invention. The foregoing embodiments may be implemented individually or in any combination.

14‧‧‧ display

20‧‧‧ display pixels

26‧‧‧lower polarizer

28‧‧‧ glass substrate

30E‧‧‧Metal display pixel electrode

32‧‧‧Thin film transistor layer

34‧‧‧Liquid layer

36‧‧‧Color filter structure

38‧‧‧Black masking material

38AA‧‧‧Black matrix/material/black masking material/black photoresist/black matrix material/black photoresist grid/layer

38IA‧‧‧Black matte/material/black photoresist strip/layer

40B‧‧‧Material/layer/blue filter component/blue photoresist structure

40B'‧‧‧ Zone/Layer/Blue Resistor Structure/Boundary Section/Blue Filter Component Material

40B"‧‧‧ areas/blue filter material/layer/blue photoresist/blue photoresist structure/grid pattern

40G‧‧‧Green filter component structure

40R‧‧‧Red filter component structure

42‧‧‧Color filter layer substrate

44‧‧‧Color filter layer

46‧‧‧Upper polarizer

47‧‧‧Indium tin oxide layer

49‧‧‧Transparent finish

50‧‧‧Inner/inner surface

52‧‧‧Viewer

54‧‧‧ Direction

61‧‧‧ vertical line

63‧‧‧ vertical line

65‧‧‧ vertical line

AA‧‧‧ area of action

IA‧‧‧inactive area

Z‧‧‧ direction

Claims (20)

A display having an active region surrounded by an inactive region, comprising: a thin film transistor layer; a color filter layer substrate; a liquid crystal material layer interposed in the thin film transistor layer and the color filter Between the sheet substrates; a black matrix on the color filter layer substrate, wherein the black matrix has an opening; and an array of color filter elements, each of the color filter elements One of the openings overlaps, wherein the black matrix includes a blue photoresist structure grid and a black photoresist structure overlap alignment grid, and the color filter elements are inserted into the blue light Between the resistive structure grid and the black photoresist structure grid. The display item 1 of claim 1, further comprising: a black mask in the inactive area, wherein the black mask comprises a blue photoresist layer covered with a black photoresist layer. The display of claim 2, wherein the color filter elements comprise blue filter elements, green filter elements, and red filter elements. The display of claim 3, wherein the green filter elements have edge portions that overlap an edge portion of the blue filter elements. The display of claim 4, wherein the red filter elements have edge portions that overlap the edge portions of the green filter elements. The display of claim 5, wherein the red filter elements have edge portions that overlap an edge portion of the blue filter elements. The display of claim 3, wherein the red filter elements have edge portions that overlap an edge portion of the blue filter elements. The display of claim 7, wherein the green filter elements have edge portions that overlap the edge portions of the red filter elements and the edge portions of the blue filter elements. The display of claim 1, further comprising an upper polarizing layer and a lower polarizing layer, wherein the thin film transistor layer, the color filter layer substrate, and the liquid crystal layer are interposed between the upper polarizing layer and the lower polarizing layer. The display of claim 9, further comprising an indium tin oxide layer between the upper polarizer and the color filter layer substrate. The display of claim 10, wherein the color filter layer substrate comprises a glass layer. The display of claim 11, wherein the thin film transistor layer comprises a display pixel electrode. A display comprising: a liquid crystal material layer; a plurality of display layers, light passing through the plurality of display layers, wherein the display layers comprise a color filter layer substrate having an inner surface facing the liquid crystal material layer; And an array of color filter elements on the inner surface, wherein the color filter element array comprises a red filter element, a green filter element, and a blue filter element; and a black matrix, On the color filter layer substrate, wherein the black matrix comprises a grid of blue polymer material on the inner surface, at least some overlapping color filter component materials on the grid of blue polymer material, and A grid of black polymer material on the overlapping color filter component material. The display of claim 13, wherein the color filter component material comprises the color The edge portion of the color filter element. The display of claim 14, wherein the plurality of display layers have an active area containing a display pixel array and have an inactive boundary surrounding the active area, wherein the display further comprises one of the inactive boundaries Material layer. A display according to claim 15 wherein the layer of blue polymeric material is formed on the inner surface, the display further comprising a layer of black polymeric material on the blue polymeric material. The display of claim 16, wherein the blue polymer material grid comprises at least some blue photoresist patterned by a halftone mask. A liquid crystal display comprising: a thin film transistor layer having a thin film transistor on a film substrate layer; a color filter layer having a color filter layer substrate; and a liquid crystal material layer Between the thin film transistor layer and the color filter layer, wherein the color filter layer comprises a black shielding layer, wherein the black shielding layer comprises a blue photoresist grid and a black photoresist alignment grid. Wherein the blue photoresist grid and the black photoresist grid have openings, wherein the color filter layer comprises an array of color filter elements, the color filter elements including red and green overlapping the openings And a blue filter element, wherein at least a portion of the color filter elements are interposed between the black photoresist grid and the blue photoresist grid, and wherein the color filter elements and the black The photoresist grid is covered with a finish. The liquid crystal display of claim 18, wherein the openings comprise rectangular openings, and wherein the blue filter elements comprise edge portions between the blue photoresist grid and the black photoresist grid. The liquid crystal display of claim 18, further comprising: a polarizer; and an indium tin oxide layer between the polarizer and the color filter substrate layer.